From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754653AbdKINeM (ORCPT ); Thu, 9 Nov 2017 08:34:12 -0500 Received: from mailout1.samsung.com ([203.254.224.24]:35724 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753406AbdKINeK (ORCPT ); Thu, 9 Nov 2017 08:34:10 -0500 DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.samsung.com 20171109133408epoutp019fa0955068146699c00733218cfab0a9~1bjqoWbQ71633216332epoutp01Z X-AuditID: b6c32a37-f0bff70000001049-8e-5a04594faf16 From: Bartlomiej Zolnierkiewicz To: Stefan Agner Cc: shawnguo@kernel.org, plagnioj@jcrosoft.com, s.hauer@pengutronix.de, Ying.Liu@freescale.com, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, LW@karo-electronics.de, fabio.estevam@freescale.com, max.krummenacher@toradex.com, mauro.salvini@smigroup.net Subject: Re: [PATCH] video: fbdev: mxsfb: fix pixelclock polarity Date: Thu, 09 Nov 2017 14:34:06 +0100 Message-id: <17182140.Z5dLF1tZkm@amdc3058> User-Agent: KMail/4.13.3 (Linux/3.13.0-96-generic; KDE/4.13.3; x86_64; ; ) In-reply-to: MIME-version: 1.0 Content-transfer-encoding: 7Bit Content-type: text/plain; charset="us-ascii" X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprDKsWRmVeSWpSXmKPExsWy7bCmrm5AJEuUweMnjBazunQtTvR9YLW4 vGsOm8WBJ8vZLI4uOMhk8bqN02LdwxdMFn+3b2KxeLFF3GLzunZ2iydPTBy4PRZ/v8fs8e9w P5PHqwt3WDzmT3/E7LFpVSebR/9fA4/dp2Yyemx65eHxeZNcAGcUl01Kak5mWWqRvl0CV8ab BReYC3rkK879ecLcwDhdoouRk0NCwETiwaZnrCC2kMAORomOjUA2F5D9nVFiw9c+FpiiM28b 2SGKNjBKfN+VC1H0lVHi38lNYEVsAlYSE9tXMYLYIgJKEl8efGYGKWIWmMAk0XnvEFi3sICj xNdzc8AaWARUJaZvO8AEYvMKaEmc7LsIdoaogJfEln3tYHFOAQuJvUdfMULUCEr8mHwPrJdZ QF5i3/6prBC2jsTZY+sYQZZJCHxmk1j5vosN4mwXiY1zb7JD2MISr45vAbI5gGxpiUtHbSHC 0xkltv+WgOjdzCixavcEqHpricPHL0It4JN497WHFaKXV6KjTQiixEPiTNdrqFWOEk9uzGSG hNA9oDnd8hMYZWchOXsWkrNnITl7ASPzKkax1ILi3PTUYsMCY73ixNzi0rx0veT83E2M4DSj Zb6DccM5n0OMAhyMSjy8L1YxRwmxJpYVV+YeYpTgYFYS4RV5CxTiTUmsrEotyo8vKs1JLT7E KM3BoiTOK7b+WoSQQHpiSWp2ampBahFMlomDU6qB0TzMOtfEX+x+0NULjG7tny6GW+rP2XDJ Pl22ZIG+upW1zwMmyWmzzaz28+a5tHY4zlL3qmQvKzj3a+vptXKqbLNKLukd493P11t/ZfFV Eynrx61uXd8UNGvWXZlecCLpg0T6/q9pM2OLDuYkvdDs0vmx6+ncKf0c7fIVMe/jnjkGB65Y tUNUiaU4I9FQi7moOBEAF82qpC8DAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrBLMWRmVeSWpSXmKPExsVy+t9jQV3/SJYog6vHdCxmdelanOj7wGpx edccNosDT5azWRxdcJDJ4nUbp8W6hy+YLP5u38Ri8WKLuMXmde3sFk+emDhweyz+fo/Z49/h fiaPVxfusHjMn/6I2WPTqk42j/6/Bh67T81k9Nj0ysPj8ya5AM4oLpuU1JzMstQifbsErow3 Cy4wF/TIV5z784S5gXG6RBcjJ4eEgInEmbeN7F2MXBxCAusYJZ7d3swM4XxllPjRtIAdpIpN wEpiYvsqRhBbREBJ4suDz2BFzAITmCSWzFvPDJIQFnCU+HpuDguIzSKgKjF92wEmEJtXQEvi ZN9FVhBbVMBLYsu+drA4p4CFxN6jrxghtnUxSmxbD9HMKyAo8WPyPTCbWUBeYt/+qawQtpbE +p3HmSYw8s9CUjYLSdksJGULGJlXMUqmFhTnpucWGxUY5qWW6xUn5haX5qXrJefnbmIExse2 w1p9OxjvL4k/xCjAwajEw+uwljlKiDWxrLgy9xCjBAezkgivyFugEG9KYmVValF+fFFpTmrx IUZpDhYlcd7beccihQTSE0tSs1NTC1KLYLJMHJxSDYwBmxs4qvrZm68YSv4REvVUm+16Jr2r ep9I7I4vortm63x85z/LK3jTwtd706dtnStm0xDyRuJQsZtf6oroLGanI/9Xpsh7btqUstsu wWmpw65vtat4j0uvFHNM6Gp0155XvsjuhsOzFOOJ8wJEcs+sm7sq5XmqszDjjz0sm9kfVTjw Xpud/EmJpTgj0VCLuag4EQC7emRqiwIAAA== X-CMS-MailID: 20171109133407epcas1p23f7ebf05f0d20e00ef56cf64425bdb60 X-Msg-Generator: CA CMS-TYPE: 101P X-CMS-RootMailID: 20171109133407epcas1p23f7ebf05f0d20e00ef56cf64425bdb60 X-RootMTR: 20171109133407epcas1p23f7ebf05f0d20e00ef56cf64425bdb60 References: <1453771756-5418-1-git-send-email-stefan@agner.ch> <1542360.CFa2kFFNPO@amdc3058> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday, October 17, 2017 06:01:58 PM Stefan Agner wrote: > On 2017-10-17 15:56, Bartlomiej Zolnierkiewicz wrote: > > Hi, > > > > Stefan/Shawn: > > > > Should I merge this patch? It seems to be still needed: > > > > https://www.spinics.net/lists/linux-fbdev/msg23112.html > > In my opinion yes, it fixes an issue... > > FWIW, I normally use the DRM driver when using mainline which does not > suffer from this issue, so I did not mind much that this fix never made > it... I queued your patch (with Shawn's ACK) for 4.15, thanks! Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics > -- > Stefan > > > > > Best regards, > > -- > > Bartlomiej Zolnierkiewicz > > Samsung R&D Institute Poland > > Samsung Electronics > > > > On Friday, May 06, 2016 01:29:59 PM Stefan Agner wrote: > >> Hi Shawn, > >> > >> On 2016-01-25 17:29, Stefan Agner wrote: > >> > The PIXDATA flags of the display_flags enum are controller centric, > >> > e.g. NEGEDGE means the controller shall drive the data signals on > >> > pixelclocks negative edge. However, the drivers flag is display > >> > centric: Sample the data on negative (falling) edge. > >> > > >> > Therefore, change the if statement to check for the POSEDGE flag > >> > (which is typically not set): > >> > Drive on positive edge => sample on negative edge > >> > >> Any comment on that patch? > >> > >> -- > >> Stefan > >> > >> > >> > > >> > Signed-off-by: Stefan Agner > >> > --- > >> > Hi all > >> > > >> > Shawn, I would like to have at least your Ack on this before merge. > >> > > >> > It seems that this has been wrong since the driver is able to use > >> > the timings from the device tree, introduced with 669406534b4a > >> > ("video: mxsfb: get display timings from device tree"). > >> > > >> > Not sure how many device trees actually specify the wrong pixel clock > >> > polarity due to that. At least the initial flag convertion from the > >> > old platform data structures done with 0d9f8217db15 ("ARM: mxs: move > >> > display timing configurations into device tree") seems to be affected > >> > and would need to be changed accordingly... > >> > > >> > Not sure how we should handle this, maybe just invert all > >> > pixelclk-active properties where the mxsfb driver is in use...? > >> > > >> > -- > >> > Stefan > >> > > >> > drivers/video/fbdev/mxsfb.c | 13 +++++++++++-- > >> > 1 file changed, 11 insertions(+), 2 deletions(-) > >> > > >> > diff --git a/drivers/video/fbdev/mxsfb.c b/drivers/video/fbdev/mxsfb.c > >> > index 4e6608c..38898a9 100644 > >> > --- a/drivers/video/fbdev/mxsfb.c > >> > +++ b/drivers/video/fbdev/mxsfb.c > >> > @@ -150,7 +150,7 @@ > >> > #define STMLCDIF_24BIT 3 /** pixel data bus to the display is of 24 > >> > bit width */ > >> > > >> > #define MXSFB_SYNC_DATA_ENABLE_HIGH_ACT (1 << 6) > >> > -#define MXSFB_SYNC_DOTCLK_FALLING_ACT (1 << 7) /* negtive edge sampling */ > >> > +#define MXSFB_SYNC_DOTCLK_FALLING_ACT (1 << 7) /* negative edge sampling */ > >> > > >> > enum mxsfb_devtype { > >> > MXSFB_V3, > >> > @@ -788,7 +788,16 @@ static int mxsfb_init_fbinfo_dt(struct mxsfb_info *host, > >> > > >> > if (vm.flags & DISPLAY_FLAGS_DE_HIGH) > >> > host->sync |= MXSFB_SYNC_DATA_ENABLE_HIGH_ACT; > >> > - if (vm.flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE) > >> > + > >> > + /* > >> > + * The PIXDATA flags of the display_flags enum are controller > >> > + * centric, e.g. NEGEDGE means drive data on negative edge. > >> > + * However, the drivers flag is display centric: Sample the > >> > + * data on negative (falling) edge. Therefore, check for the > >> > + * POSEDGE flag: > >> > + * drive on positive edge => sample on negative edge > >> > + */ > >> > + if (vm.flags & DISPLAY_FLAGS_PIXDATA_POSEDGE) > >> > host->sync |= MXSFB_SYNC_DOTCLK_FALLING_ACT; > >> > > >> > put_display_node: